Remove the configurable Hide Server Address Feature

There is config option ``hide_server_address_states`` which accept the list of
server states for which server address needs to be hidden. Server Show and List Detail
API return the empty dict for server address field if server is in those states.

Let's remove this configurable options and have hard coded server states to hide address.

Approved for Queens. The spec was approved on Sept 20, I just wasn't tracking this for Queens apparently. -- mriedem 20171207

Considering this complete for Queens since https://review.openstack.org/#/c/526297/ is merged which deprecates the associated config option and policy rule, which we can then remove in the Rocky release. -- mriedem 20171220